The invention provides a grounding coplanar waveguide diplexer antenna, aims to realize integrated design of a diplexer and an antenna and aims to improve electromagnetic shielding performance on thecondition that isolation of the diplexer is guaranteed. The grounding coplanar waveguide diplexer antenna comprises a medium substrate, and two open loop resonators, two feed wires and an upper grounding board which are arranged at one side of an upper surface of the medium substrate, a radiation patch arranged at the other side, and a lower grounding board printed on a lower surface of the mediumsubstrate, wherein the upper grounding board and the lower grounding board are connected through a side edge patch, the two open loop resonators are connected with the upper grounding board through grounding stub wires, electrical coupling is formed at an opening, a right transmission zero point of a channel is formed, the two grounding stub wires form magnetic coupling, a left transmission zeropoint of the channel is formed, and the upper grounding board, the lower grounding board, the two feed wires, the side edge patch and the two resonators form a grounding coplanar waveguide structure.The antenna is advantaged in that the volume is small, electromagnetic shielding performance is good, and the antenna can be applied to a micro radio frequency front system.